I figured out why gifs and jpgs had been opening with Netscape on my work computer, even though they still had Photoshop icons. Apparently this is part of Netscape setting itself as the default browser. I edited the file type thingys so that they would open in Photoshop. Then when I started Netscape, it said it was not the default browser, and would I like to make it so? Confused, I clicked Yes. And sure enough, the image file types info went back to "open with Netscape". So I re-edited it and this time told Netscape not to make itself the default browser, and not to check next time either.
I mean, default browser, yes. Default image viewer? WTF?
I mean, default browser, yes. Default image viewer? WTF?